Dr Klaus van de Weyer has worked on macrophytes for 25 years and is a recognised expert in his field. He is a member of a number of different German committees (CEN/German working group DIN-NAW DIN-NA 119-01-03-05-06 Working Group Biological-ecological methods, ICPR), an assigned expert for aquatic plants within the Society For the Research on the German Flora (www.flora-deutschlands.de) and one of the coordinators of the Charophyte Atlas and the Red Data book of Charophytes in Germany. Dr Klaus van de Weyer is member of the IUCN - Freshwater Plant Specialist Group. Further, Dr Klaus van de Weyer is involved in the data collection on alien aquatic macrophytes in Germany (HUSSNER et al. 2008, VAN DE WEYER & HUSSNER 2008). During his work he has designed different assessment systems for macrophytes in riverine and lacustrine ecosystems, comprising natural as well as artificial habitats, according to the Water Frame Work Directive in Germany (VAN DE WEYER 2006, 2008, VAN DE WEYER et al. 2009). Dr Klaus van de Weyer has published several papers concerning macrophyte ecology, distribution and their threatened status in Germany (www.lanaplan.de). Moreover, he is working as reviewer for different journals. Dr Klaus van de Weyer has provided training courses on macrophyte ecology and identification since the year 2000.